LAUSR

A novel iron(III) cellulose nanocomposite bead was synthesized via sol-gel technique and was used for removal via adsorption of Cr(VI) from laboratory as well as real sample. Characterization of the bead for bulk, surface and thermal properties was made. The adsorption process was optimized for operating variables viz. pH, contact time, initial Cr(VI) concentration, FeCNB dose as well as temperature in batch operation. The equilibrium was achieved within 5 h of contact time and 94% adsorption occurred corresponding to an initial Cr(VI) concentration of 100 mg L−1 at 300 K. The process follows the Langmuir isotherm and is spontaneous, endothermic as well as random in nature. The second order rate equation most suitably describes the adsorbate-adsorbent interaction in the present case. Elution of Cr(VI) was found effective using 0.1 mol L−1 NaOH. The synthesized bead was recycled and reused for five successive retention-elution operations. The process was successfully applied in removing Cr(VI) from tannery effluent.